It really does depend. There are many styles that I think benefit from a simpler grain bill. Including some that you wouldn't expect... many Belgian styles seem complex but get their flavor from the yeast or rich candy syrup, and can taste muddled with a heavy malt bill. On the other hand, for a stout layering some complexity in the grain bill wouldn't be a bad thing. You also don't have an overabundance of crystal malts or other pronounced flavors like aromatic, biscut, etc. Different kinds of 2-row, brown/amber malt, and even chocolate/black malts are not all that different, so I think your recipe is simpler than you give it credit for
I've never tasted Mr. Rainer hops, nor have I done a hop-bursted stout, but that's another topic entirely.